An aircraft can include a potable water system having, among other things, a water storage container (e.g., a tank). While the exact amount of water within such a container is usually not important, it is often necessary (or at least helpful) to have a generally indication of its current capacity. To this end, sensing devices can be installed to sense when the water level reaches, for example, a level corresponding to its full capacity, a level corresponding to its empty capacity, and/or a level corresponding to an intermediate capacity (e.g., half-full).